$(function(){
  document.documentElement.addEventListener('touchstart', function (event) {
    if (event.touches.length > 1) {
      event.preventDefault();
    }
  }, false);
  var lastTouchEnd = 0;
  document.documentElement.addEventListener('touchend', function (event) {
    var now = Date.now();
    if (now - lastTouchEnd <= 300) {
      event.preventDefault();
    }
    lastTouchEnd = now;
  }, false);
})